document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=400689>Question 400689</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A sight seeing boat travels an average speed of 18 mph in the calm water of a large lake.  The same boat is used for sight-seeing in a near by river.  In the river, the boat travels 2.6 downstream (with the current) in the same amount of time it takes to travel 2.1 miles upstream (against the current).  Write an equation that can be used to solve the problem and find the current of the river.\r<BR>\n" );
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document.write( "We have tried t=d/s to get the time 2.6/18+r = 2.1/18-r then we get 46.80 - 2.6r = 37.80 + 2.1r I get 18 as the current worked out but if I put 18 back in I will get a 0 denomintor.  This can't be right? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #283634 by </B><A HREF=/tutors/aboutme.mpl?userid=Alan3354><B>Alan3354(69443)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Alan3354><IMG SRC=http://www.algebra.com/images/aboutme-small.gif BORDER=0 alt=\"About Me\" VALIGN=MIDDLE></A>&nbsp;<IMG SRC=http://www.algebra.com/cgi-bin/show-face.mpl?user=Alan3354><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=283634\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> A sight seeing boat travels an average speed of 18 mph in the calm water of a large lake. The same boat is used for sight-seeing in a near by river. In the river, the boat travels 2.6 downstream (with the current) in the same amount of time it takes to travel 2.1 miles upstream (against the current). Write an equation that can be used to solve the problem and find the current of the river. <BR>\n" );
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document.write( "c = current speed<BR>\n" );
document.write( "t = d/r<BR>\n" );
document.write( "t = 2.1/(18 - c) = 2.6/(18 + c)<BR>\n" );
document.write( "2.1/(18 - c) = 2.6/(18 + c)<BR>\n" );
document.write( "2.1(18+c) = 2.6(18-c)<BR>\n" );
document.write( "37.8 + 2.1c = 46.8 - 2.6c<BR>\n" );
document.write( "4.7c = 9<BR>\n" );
document.write( "c = 90/47 mph<BR>\n" );
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document.write( "We have tried t=d/s to get the time 2.6/18+r = 2.1/18-r then we get <BR>\n" );
document.write( "46.80 - 2.6r = 37.80 + 2.1r <BR>\n" );
document.write( "I get 18 as the current <BR>\n" );
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document.write( "I don't know how you got 18 as the current. </SPAN>\n" );
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